1. Field of the Invention
The invention concerns a method for the quantitative analysis of sample liquids by irradiating a sample that has been essentially freed of solvent and detecting the radiation that is diffusely reflected from the sample and sample carrier. In addition the invention includes a system for the analysis of sample liquids with which samples that have been essentially freed of solvent that are located on a sample carrier are irradiated and the radiation emitted from the sample is detected with a detection device. The invention additionally encompasses a sample carrier for use in a system according to the invention in which a diffusely reflecting metal layer is present on a carrier.
2. Description of the Prior Art
Methods for the qualitative analysis of sample liquids are known in the state of the an in which solids, thin layer chromatograms or residues of drying are illuminated with infrared radiation and the reflected radiation is analysed in order to obtain information on substances in the sample. In the disclosure DE-A-42 33 321 a microanalytical method is described in which the sample liquid is applied onto a plastic carrier and subsequently dried up. Measures are described in this disclosure which are aimed to achieve a layer thickness that is as large as possible and as flat a structure as possible of the residue of drying. Only pan of the residue of drying is irradiated with infrared radiation using the described system and the specularly reflected radiation is analysed. Since the radiation passes through only pan of the residue of drying a quantitative analysis is only possible when exactly defined dimensions of the residue of drying can be guaranteed which in practice is very time-consuming.